Browsing by Author "Morais, Rui"
Now showing 1 - 10 of 19
Results Per Page
Sort Options
- Antiadhesive and antibiofilm effect of Malvidin -3- glucoside and Malvidin -3- glucoside/neochlorogenic acid mixtures upon staphylococcusPublication . Silva, Sara; Costa, Eduardo; Veiga, Mariana; Morais, Rui; Calhau, Conceição; Pintado, Manuela
- Antiadhesive and antibiofilm effect of malvidin-3-glucoside and malvidin-3-glucoside/neochlorogenic acid mixtures upon staphylococcusPublication . Silva, Sara; Costa, Eduardo M.; Machado, Manuela; Morais, Rui; Calhau, Conceição; Pintado, ManuelaSeveral reports on the biological activity of anthocyanin-rich extracts have been made. However, despite the association of said activity with their anthocyanin content, to the best of our knowledge, there are no previous works regarding the antimicrobial, antibiofilm and/or antiadhesive properties of anthocyanins alone. Therefore, the present work aimed to determine the effects of malvidin-3-glucoside, a major component of a previously reported extract, and the impact of its association with neochlorogenic acid (the only non-anthocyanin phenolic present in said extract), upon several Staphylococcus strains with varying resistance profiles. Results show that, while malvidin- 3-glucoside and malvidin-3-glucoside/neochlorogenic acid mixtures were unable to considerably inhibit bacterial growth after 24 h, they still possessed an interesting antibiofilm activity (with reductions of biofilm entrapped cells up to 2.5 log cycles, metabolic inhibition rates up to 81% and up to 51% of biomass inhibition). When considering the bacteria’s capacity to adhere to plain polystyrene surfaces, the inhibition ranges were considerably lower (21% maximum value). However, when considering polystyrene surfaces coated with plasmatic proteins this value was considerably higher (45% for adhesion in the presence of extract and 39% for adhesion after the surface was exposed to extract). Overall, the studied anthocyanins showed potential as future alternatives to traditional antimicrobials in adhesion and biofilm formation prevention.
- Biodegradation of p-nitrophenol by microalgaePublication . Lima, Sofia A. C.; Castro, Paula M. L.; Morais, RuiA study was made on the use of a mixed microalgal consortium to degrade p-nitrophenol. The consortium was obtained from a microbial community in a waste container fed with the remains and by-products of medium culture containing substituted aromatic pollutants (nitrophenols, chlorophenols, fluorobenzene). After selective enrichment with p-nitrophenol (p-NP), followed by an antibiotic treatment, an axenic microalgal consortium was recovered, which was able to degrade p-nitrophenol. At a concentration of 50 mg L−1, total degradation occurred within 5 days. Two species, Chlorella vulgaris var. vulgaris f. minuscula and Coenochloris pyrenoidosa, were isolated from the microalgal consortium. The species were able to accomplish p-NP biodegradation when cultured separately, although Coenochloris pyrenoidosa was more efficient, achieving the same degradation rate as the original axenic microalgal consortium. When Coenochloris pyrenoidosa was associated with Chlorella vulgaris in a 3:1 ratio, complete removal of the nitro-aromatic compound occurred within three days. This is apparently the first report on the degradation of a nitro aromatic compound by microalgae.
- Carotenoids, foodstuff and human healthPublication . Raposo, M. F. de J; Mendes-Pinto, M. M.; Morais, Rui
- Comparative analysis of two algae: impact on bioavailability, health benefits, and matrix variationsPublication . Coelho, Marta; Rocha, Helena; Morais, Rui; Gomes, Ana M.; Pintado, Manuela
- Dual-study exploration: impact of extraction methods on bioavailability, health-related properties, and matrix variationsPublication . Coelho, Marta; Rocha, Helena R.; Morais, Rui; Gomes, Ana M.; Pintado, Manuela E.Objective: This study aimed to evaluate how digestion affects bioactive compounds (BC) in algae matrix and derived extracts, focusing on Osmundea pinnatifida and Codium spp. It also examined the impact of non-absorbed fractions on gut microbiota growth (GMG) and metabolic activity. Methods: The study investigated the influence of hexane extraction on the bioavailability of bioactive compounds (BC) in algae using the INFOGEST in vitro model. Carotenoids, assessed via HPLC, were studied, alongside health-related activities like antioxidant (ABTS and ORAC), anti-hypertensive, and anti-inflammatory methods, and gut microbiota analysis (GMG using human faecal samples analysed by PCR in real-time). Results: In the algae study, the extraction method significantly influenced bioaccessibility. Gastrointestinal digestion simulation revealed varied carotenoids along the gastrointestinal tract (GIT), with only 2.49% beta-carotene absorption. Carotenoids, specially, lycopene, beta- carotene, beta-cryptoxanthin and lutein, in both extracts experienced significant decreases during GIT, particularly under stomach conditions. O. pinnatifida showed no detectable carotenoids, indicating compromised bioaccessibility in complex algae matrices without prior lysis treatment. Carotenoid extracts exhibited noteworthy antioxidant and antidiabetic activities, with lutein demonstrating superiority in the absorbed fraction. Both extracts exhibited high anti- inflammatory and moderately anti-hypertensive activities compared to algae matrices. Relatively to gut microbiota modulation, impact of digested algae highlighted the relative abundance of Bacteroides genus, while for the extracts it was the Bifidobacterium. Conclusions: These results emphasize the crucial role of extraction methods and digestion conditions in shaping the bioavailability and health-related attributes of bioactive compounds in algae, offering valuable insights for further research and application in the realm of functional foods and nutraceuticals.
- Dual-study exploration: impact of extraction methods on bioavailability, health-related properties, and matrix variationsPublication . Coelho, Marta; Rocha, Helena; Morais, Rui; Gomes, Ana M.; Pintado, ManuelaIntroduction: Osmundea pinnatifida and Codium spp. are rich in Bioactive Compounds (BC), which have been linked to numerous health benefits, including antioxidant, anti-hypertensive, and anti- inflammatory effects. However, the extent to which these compounds can be absorbed and utilized by the body is largely dependent on how they are affected by the process of digestion. Objectives: By using the INFOGEST in vitro model, this study provides valuable insights into how hexane extraction influences the bioavailability of these BC. Furthermore, it examines the impact of non- absorbed fractions on gut microbiota growth (GMG). In essence, this study contributes significantly to our understanding of the nutritional potential of algae and the role of digestion in unlocking their health benefits. Results: The simulation revealed varied carotenoids along the gastrointestinal tract, with only 2.49% beta-carotene absorption. Carotenoids, especially lycopene, beta-carotene, beta-cryptoxanthin, and lutein, experienced significant decreases during passage through the gastrointestinal tract, particularly under stomach conditions. Carotenoid extracts exhibited noteworthy antioxidant and antidiabetic activities. Os. pinnatifida showed no detectable carotenoids, indicating compromised bioaccessibility in complex algae matrices without prior lysis treatment. Conclusions: The extraction method used in the algae study significantly influenced the bioaccessibility of nutrients and BC. Both extracts exhibited high anti-inflammatory and moderate anti-hypertensive activities compared to algae matrices. The impact of digested algae highlighted the relative abundance of the Bacteroides genus. The findings underline the importance of extraction techniques and digestion conditions in determining the bioavailability and health benefits of bioactive compounds in algae. This provides important perspectives for future studies and uses in the field of functional foods and nutraceuticals.
- Estudo do efeito de cinetina e 2,4-D no crescimento de Dunaliella salinaPublication . Guadalpi, Ana; Barbosa, Maria João; Raposo, F.; Morais, Rui
- Functional vegetable-based sausages for consumption by childrenPublication . Burri, Solange; Tato, Isabel; Nunes, Maria Leonor; Morais, RuiThe dislike food preferences that children registered regarding vegetables and fish compromise the exposure to those iodine sources and may contribute to cause a nutritional deficiency in this micronutrient, causing serious damage of the brain and the central nervous system. Functional foods are becoming well-established in the market, focused on by an adult consumer more interested in healthy eating habits but without the motivation to optimize natural food preparation or to promote a wide variety of food in his diet. This article presents evidence of a new functional product concept, 100% vegetable, fermented soya based and salted by red algae, that was approved by 900 parents who chose the senso-rial features: distinctive aroma (57.9%), soft texture (38.4%), sausage shape (21%) and attractive color (77.9%). Three different varieties were developed: carrot (50% w/w), sugar-beet (50% w/w) and tomato (40% w/w) mini sausages, with tofu (20% w/w) and 0.8% (w/w) of seaweed, reflecting trends that the younger consumer demands. The sensorial tests performed, after quality control assays, received very satisfactory acceptance by the potential buyer.
- Impact of gastrointestinal digestion on the bioactivity and bioaccessibility of carotenoids and phenolic compounds from algaePublication . Coelho, Marta; Rocha, Helena; Cunha, Sara; Morais, Rui; Gomes, Ana Maria; Pintado, Manuela